Which products and versions are affected by CVE-2020-27838?

Affected: Keycloak (Redhat) versions >= keycloak 13.0.0; Single Sign-On (Redhat) versions 7.0; org.keycloak:keycloak-core (maven). The full list is in the CVE brief.

Is CVE-2020-27838 being exploited in the wild?

It is not listed in any known-exploited vulnerabilities catalog.

Is CVE-2020-27838 in the CISA KEV catalog?

No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

Is there a public exploit for CVE-2020-27838?

No public exploit code is known.

Is there a fix for CVE-2020-27838?

Fixed versions are available, including Keycloak 13.0.0-1, Keycloak 13.0.0, org.keycloak:keycloak-core 13.0.0.

How urgently should CVE-2020-27838 be patched?

Brandefense priority: routine patching, as no exploitation is known and its severity is moderate or low.

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Vulnerability Intelligence

CVE-2020-27838

Medium

Keycloak discloses information without authentication

Published May 24, 2022 · Updated Aug 7, 2026 · Also known as GHSA-pcv5-m2wh-66j3

Key Facts

Routine patching

CVE-2020-27838 is a medium-severity vulnerability (CVSS 6.5 v3.1) affecting Keycloak (Redhat), Single Sign-On (Redhat), org.keycloak:keycloak-core (maven).
It is not listed in any known-exploited vulnerabilities catalog. No public exploit code is known.
EPSS estimates a 18% probability of exploitation in the next 30 days.
Fixed versions are available, including Keycloak 13.0.0-1, Keycloak 13.0.0, org.keycloak:keycloak-core 13.0.0.
Brandefense priority: routine patching, as no exploitation is known and its severity is moderate or low.

CVSS v3.1

6.5

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

EPSS (30-day exploit likelihood)

18%

Higher than 97.1% of all scored CVEs

Exploited in the wild

No known

Not in a known-exploited catalog

Public exploit code

None known

Get the full CVE-2020-27838 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

Description

A flaw was found in keycloak in versions prior to 13.0.0. The client registration endpoint allows fetching information about PUBLIC clients (like client secret) without authentication which could be an issue if the same PUBLIC client changed to CONFIDENTIAL later. The highest threat from this vulnerability is to data confidentiality.

Affected Products

5 affected entries in total

Product	Affected versions	Fixed in
KeycloakRedhat	>= keycloak 13.0.0	13.0.0
Single Sign-OnRedhat	7.0	n/a
org.keycloak:keycloak-coremaven	See advisory	13.0.0

Patched Releases

Keycloak

13.0.0-1, 13.0.0

org.keycloak:keycloak-core

13.0.0

Timeline

Publicly disclosed
May 24, 2022
Last updated
Aug 7, 2026

Weakness Type

CWE-287 Improper Authentication

References

FAQ

Common Questions.

A flaw was found in keycloak in versions prior to 13.0.0.
Affected: Keycloak (Redhat) versions >= keycloak 13.0.0; Single Sign-On (Redhat) versions 7.0; org.keycloak:keycloak-core (maven). The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Keycloak 13.0.0-1, Keycloak 13.0.0, org.keycloak:keycloak-core 13.0.0.
Brandefense priority: routine patching, as no exploitation is known and its severity is moderate or low.

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